Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety. The description adds output details but no deeper behavioral context (e.g., rate limits, URL format quirks). It adds minimal value beyond annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single, well-structured sentence packs the primary verb, resource, and expected outputs without fluff. Every word earns its place, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (one parameter, no output schema), the description sufficiently lists the return contents (fields, geometry, count, capabilities). A slight gap is that 'capabilities' is not explained, but this is minor for a schema introspection tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

There is only one parameter (url) with 100% schema description coverage. The description repeats 'by url' but does not add extra meaning like accepted URL forms or error conditions. Baseline 3 is appropriate as the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses the specific verb 'Get' and clearly identifies the resource: an ArcGIS Feature/Map Service layer's schema. It enumerates the exact outputs (fields, geometry type, record count, capabilities), distinguishing it from sibling tools like query_layer, which likely retrieves data rather than schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase 'by url' establishes the clear context for when to use this tool (when you have a layer URL and need schema information). It does not explicitly list alternatives or exclusions, but the scope is unambiguous for a schema retrieval operation.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.